Electric furnace.



Y BESTAVAILABLE COP` RJ. MAOHALSKE.

ELECTRIC FURNACE. APPLICATION HLED JUNE 27, 191s,

Patented June 9, 1914.

" oFFiCE.

. rLoREN'rINgJ. MAcHaLsKE, or' PtA'rTsBURG, -EW Yoran, ass1GNoR, BYv'MESNE ASSIGNMENTS, To AMERICAN FEBRQLECTRIDE coRPoRATIoN, orPLATTSBURG, YNEW Yomeli' coRPoaATIoN or imwvonx. I Y

To all '2h/tnt it may concern s Beit known that, FLORmiriNE'JrMkoHLiLsir, a citizen -of theUnite'- qstatea re-l siding fat.'Plattsburg, Clinton; gc'ounty, New

' 1o` f urnacejfor smeltig o res,` 1ncre particularly ironvores,h'ayi'nga permanent lining which is-practicallyY unaffected by ,themolten metal York, have inventodcertain new. use ful`Irnpro \"eIue i1ts-in Electric-Furnaces, of whichherfollowig is 'a 'f ullgclear,,xactdesc'ription M inventioi'rrelatesto .electric furnaces and' as'forits 'object to provide an. electric and" doesanotncombine `therewith 'soas to produce 'impurities v tlliereinl ln electrically]sinelting. ores,especially where the furnace charges-are of basic charf actor', anordinary carbon lining V will notresistl tl 1e acti0n `of themolten-metal or the. 'slagfand alin'ing of otherfre'fractory mate- .irialslike magnesite br i"ck, "\`vhilev partly r`e-` 'sisting the action.of the slag, 'will' not resist' the action of lmolten Vironlf IyiningsV suchas; either of. those abovejriention'ed which are v25 no Wcommonly used;- destroyed veryV carbonlning is used, thecarbon'entersinto combination with the' molten metal, there by affectingits Properties-@ f eumg its vsmelting* furnace,`-where .it comes inContact with theinolteniromis madepf'electrically tenmetal;

' The -ollo'wing' '1s ai description of an em'- had -tothe-"accompanying drawings, in

whichl 'e' Figure 1V representsa cross section of a 'furnace of the;open type Fig. 2' is a plan, view of one of/tbie "electrolies, 'and`'Fig visiv trically .treated carbonV known 'as' A Referring moreparticularly to the-dra'wfings. 1 is the casing 'of' the furnace hav1ngat its bottoni a layer 4of .bricks of artificial. graphitic carbon orgraphite, namely, eleccheson graphite. The subjecting-,of ordinary car-ELEc'rRIG FURNACE.

Specification of Letters'Patent. Appiication sieqnegz, 1913,.seria1No.77s,15s.

and

bon to the heat of an electricarc converts '1t into such artificialgraphite and-,produces a Patented June 9,1914'.

substantially pure graphite product greatly I superior to nativeC'raphite formy purposes. Thelower'portionof vthe'yv'alls-of thefurnace' 1s` vcomposed of bricks of the artificial graphite. Inthedrawing's tfhetwo layers of -br1ckl-2 arefof this artificial'graphite,

posed of niao'nesite raised 'so asfto'be slightlyabove the upper surface'of the molten metalzandsurroundff .ed'at their lower-ends by the slag;The electrodesff are connected to one terminal of brickupoii-gthefwallsextenlsupWai-da di's; 'tance of; about 'six inches'.'frorutheghottoin Above the graphite brick, the .w alls" are coin# v(magnesium .carbonate)' brick,-

being a'highly refractory material Wh'icli': is practically unaffectedby the slag. g

70" intli'elcharga being'locatedluear the bottoni of the furnace atthestart,l and after the vcharge.-.has.become 'seinewhat'A heated, Y

a source -of current, while the electrode fis 'l cOniieQ'tg: dA tothe'other'jterinnal ofi ksaid source.;` The furnaceisprovided-with a tap'hole' atthe bottoni for ten metal and-ataphole 6 located just abovethegraphite portion of tbe-'Walls for 'draw- -ing o th'efslagf"- 'e "Inconnectionnith this furnace I prefer electrode yis shown in detail Q'and .3 and-lc'fonsists of afmetal sheath or casing 7- "of any desireddiameter,v preferably of sheet'i ron, Ythe'diar'nete'r whichI have usedbeing about twenty. inches. vlVit-hin this'A metal sheath or casing, andextending the '-full length thereof, are four `carbou rods-8, Y VWhich,for 'the sake of cheapness, may. be'

off ordinarycarbon, although theymay also befoffgraphite'. -The' spacewithin the casmgl surrounding the -four' carbon rods is ill'ed'v with-a.filling 9 of closely packed magnesium oXid'or dolomite (calciummagnesiumcarbonatefMgCaCzO). -I mix the; filler (ma withfsome bin ing material,such as tar or e'sium'-oxid or dolomite) silicate of' sodznthe binder,when-tar is' used, being heatedduring the mixing process. I use onlyenough of the binder to. Xform the filler (magnesium oxid or dolo-vmite) 'into a coheringmass, After the filler.

,se drawing off the mole s vto. use a special form of electrode,although vother forms may be used.= l.This'formr'o-fnace, the lower endsof the carbon rods first g nesium 'oxid (dolomite) being a slagformnoris' the metal combined therewith so as currentA and thencommunicate the heat to 1 surrounding thev saine, which thenbecomesAlower portion, which condition is' the desired rods, however, arequickly convertedinto Vgraplntic carbon or art-ilicialgraphite so thateven if they come in'contact with the tion and construction of theelectrode above.

BES

mixture is packed into the casing around E the carbon rods,the'electrode is thoroughly baked to drive-ofi any remaining moisture.The carbon rods when the electrode is in use are electrically' connectedtogether as at 10 and to the source of current. With suchan electrodewhen it is used in a furbecome highly heated by the passage of the thelower portions of the magnesium oxid a conductor of relatively' lewconductivity, with the resultthat the electrode has when in use a Averyextended'incandescent area at its condition-in a smelt-ing furnace. Theniaging element., adds to the slag formed in the fr'rnace and protectsthe lmolten metal from i lhe'carb'on. The lower ends ofthe carbon moltenm etal, they are'not attacked thereby to' be carburized. The particularcomposireferred to, while disclosed herein, is ,not claimed herein,being the subject matter of anotherY application led simultaneouslyfherewith Serial No. 770157.

In operating the furnace, the tap (3 is ordinarily left open so as' todrain olf the Copies of this patent may be obtained for slag. The tap 5is opened from time to timel described in another application ledsimultaneously herewith Serial No. 776,156, viz., a charge in whichartificial graphitepis used as the reducing or de-oxidizing agent.

What 'I claim is:

1l A furnace having its bottom and the lower portions ofits side Wallslined with artificial graphit-ic carbon and vhaving the adjacentportions of its Walls covered with magnesite. Y

`2. A furnace having its bottom andthe `lowerI portions ofits side Wallslined withl artificial graphitic carbon and having the' Aadjacentportions of its walls covered with a niagnesite lining and having tapslocated adjacent to the bottom cf the furnace and at the top of thegraphit/ic lining.

FLORENTINE J. MACHALSKE. Witnesses XV. H. CLARK, T. Gr, Horr.

ve cents each, by addressing the Commissioner of Patent. Washington, ID.C."

